1. Field of the Invention
The present invention relates to a toner dispensing method for use with an electrostatic reproducing apparatus.
2. Description of the Prior Art
In an electrostatic reproducing apparatus using a two component developer, the toner is agitated in developing device with a carrier such as iron powder so that it is frictionally charged. When the copying operation is to be performed, the toner is electrostatically trapped by the electrostatic latent image portion of a moving electrophotographically photosensitive member thereby to form a toner image. Since the toner is consumed by the copying operation, it is necessary to perform toner dispensing.
The quantity of toner to be consumed for one copy is about 30 mg at the largest. In the toner dispensing method having been practised in the prior art, therefore, when about several tens or one hundred sheets are copied, the toner is dispensed at one time in a quantity corresponding to the quantity consumed so that its blended ratio with the carrier may be maintained within a predetermined range.
If, however, the toner is dispensed in an excessive quantity at one time, it is insufficiently agitated with the carrier because it has a self-aggregating nature. The toner thus insufficiently agitated and frictionally charged is insufficiently caught by the carrier so as to cause for its scattering during the development and for the deterioration in the picture quality of the copy.
I, the inventor, have made investigations with a view to preventing the toner scattering and have found that the dispensing of the toner in a large quantity at one time will cause the aggregation and scattering of the toner, as has been described in the above.